﻿// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information
// 
// Licensed to the Apache Software Foundation (ASF) under one or more
// contributor license agreements. See the NOTICE file distributed with
// this work for additional information regarding copyright ownership.
// The ASF licenses this file to you under the Apache License, Version 2.0
// (the "License"); you may not use this file except in compliance with
// the License. You may obtain a copy of the License at
// 
// http://www.apache.org/licenses/LICENSE-2.0
// 
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// 

using System;
using System.Text;

using log4net.Layout;

namespace log4net.Util.TypeConverters
{
    /// <summary>Supports conversion from string to <see cref="PatternLayout"/> type.</summary>
    /// <remarks>
    /// <para>
    /// Supports conversion from string to <see cref="PatternLayout"/> type.
    /// </para>
    /// <para>
    /// The string is used as the <see cref="PatternLayout.ConversionPattern"/> 
    /// of the <see cref="PatternLayout"/>.
    /// </para>
    /// </remarks>
    /// <seealso cref="ConverterRegistry"/>
    /// <seealso cref="IConvertFrom"/>
    /// <seealso cref="IConvertTo"/>
    /// <author>Nicko Cadell</author>
    internal class PatternLayoutConverter : IConvertFrom
    {
        /// <summary>Can the source type be converted to the type supported by this object</summary>
        /// <param name="sourceType">the type to convert</param>
        /// <returns>true if the conversion is possible</returns>
        /// <remarks>
        /// <para>
        /// Returns <c>true</c> if the <paramref name="sourceType"/> is
        /// the <see cref="String"/> type.
        /// </para>
        /// </remarks>
        public bool CanConvertFrom(Type sourceType)
        {
            return (sourceType == typeof(string));
        }

        /// <summary>Overrides the ConvertFrom method of IConvertFrom.</summary>
        /// <param name="source">the object to convert to a PatternLayout</param>
        /// <returns>the PatternLayout</returns>
        /// <remarks>
        /// <para>
        /// Creates and returns a new <see cref="PatternLayout"/> using
        /// the <paramref name="source"/> <see cref="String"/> as the
        /// <see cref="PatternLayout.ConversionPattern"/>.
        /// </para>
        /// </remarks>
        /// <exception cref="ConversionNotSupportedException">
        /// The <paramref name="source"/> object cannot be converted to the
        /// target type. To check for this condition use the <see cref="CanConvertFrom"/>
        /// method.
        /// </exception>
        public object ConvertFrom(object source) 
        {
            string str = source as string;
            if (str != null)
            {
                return new PatternLayout(str);
            }
            throw ConversionNotSupportedException.Create(typeof(PatternLayout), source);
        }
    }
}
